//
//  Subject.h
//  Observer
//
//  Created by Shane on 17/9/18.
//  Copyright © 2017年 Shane. All rights reserved.
//

#ifndef Subject_h
#define Subject_h

class Observer;

class Subject {
public:
    virtual ~Subject();
    
    virtual void attach(Observer *) = 0;
    virtual void detach(Observer *) = 0;
    virtual void notify() = 0;
};


#endif /* Subject_h */
